This invention relates to an anti-pilling treating method for protein fiber material to prevent the development of pilling on protein fiber products such as silk and animal hair.
Generally, fiber materials are terms that comprehensively refer to fibers, intermediate products of thread, threads and fabrics. Protein fiber materials include wools such as Merino wool, lamb wool, Angora wool, cashmere, alpaca, mohair and camel, and animal hair and silk. They are superior in heat retainability and stretchability, have hygroscopicity in spite of the fact that they are water-repellent, and are less likely to be deformed since they are elastic and recoverable even if deformed. Thus they have preferable properties as woven fabrics and materials for garments.
With fiber products made of such protein fiber materials, if friction or shock is applied to fibers while wearing, short fibers or micro-fibers that form thread float up from the thread surface and tend to get tangled together, thus developing pillings. This may impair the appearance of garment products.
As a conventional anti-pilling treatment method for protein fiber materials, a method is known in which 2,6-dichloro-4-hydroxy-S-triazine or its salt is used as a treating agent (JP patent publication 2002-138369).
As a treating method for fiber (such as wool) products, a method is known in which using as a cross-linking agent a compound having a trichloropyrimidine group or a dichloropyrimidine group and anion activated groups and having aryl groups as its matrix, main and side chains of protein fiber are coupled together to form an intricate network structure to improve the form stability such as wrinkle resistance, stretchability and shrink resistance (JP patent publication 9-78451).
But in the first anti-pilling treating method using a triazine compound, since a triazine compound tends to be hydrolyzed, it is not easy to obtain fibers that have constant quality by stable treatment. Thus this method requires a high level of treating technique.
Also, in the second method, since the molecular weight of the cross-linking agent is large, it is difficult to obtain a drape having sufficient softness for the treated fiber. Thus it is difficult to manufacture fiber products of high quality.
Also, with a treating method of which the main object is to prevent felting or shrinkage, even though a weak anti-pilling effect may be accidentally obtained, pilling resistance of about level 5 in a pilling test with the method under JIS L1076 cannot be reliably obtained.
For reference, there is an anti-pilling treating method which can be used for cellulose fibers. But since fibers are damaged, this method cannot be used for protein fiber materials.
An object of this invention is to provide an anti-pilling treating method by which fiber materials that are constant in quality by stable treatment and have sufficient softness and drape can be obtained, and which provides superior pilling resistance so that high-quality protein fiber materials having pilling resistance can be stably manufactured.